Ross D. Franklin / AP

YUMA, Ariz.—Steve Alameda is Kyrsten Sinema’s dream voter. In this military town, roughly 20 miles from the Mexico border, the culture is “hard right” and “stubborn,” according to locals. The economy is heavily agricultural: Growers say they provide 90 percent of the country’s leafy greens during the winter. Alameda is a farmer who heads the local fresh-vegetable association, and he identifies as a Republican. But this year, he’s voting for Sinema for the United States Senate.

“The fact that she’s got where she’s got … that is so big in Arizona, it’s unbelievable,” he told me, after a small health-care event with the candidate. Her opponent—Martha McSally, who stumped with President Donald Trump last week—“is very partisan,” Alameda said. “It’s brutal.”

With two weeks to go until the midterm elections, this is the culmination of Sinema’s grand plan to become Arizona’s first Democratic senator in two decades. The onetime anti-war protester has spent a year carefully cultivating her moderate cred across the state, touting herself as a lawmaker who will work with “literally anyone who is willing to … get something done.” In Yuma, she spoke proudly about meeting with Trump on infrastructure and having him sign one of her bills. And she used the word bipartisan five times in four sentences as she discussed efforts to pass a farm bill in toxic Washington.

With early voting under way in Arizona, Sinema and McSally are in a dead-heat race. If Sinema wins, she will hold an important seat for embattled Senate Democrats and offer evidence that this solid red state can turn purple. But her campaign will also test a hypothesis about the Democratic Party’s future: The way to win, at least in conservative states, is to move aggressively to the middle.

[Read: A Republican victory in Arizona sets off alarms in the GOP.]

Sinema’s strategy is partly a bet on where the margin of victory for Democrats lies in elections: in the center, or on the left? Some Democrats believe that a fired-up progressive base will make the difference in tight races against Republicans. Beto O’Rourke, who is running against Republican Senator Ted Cruz in Texas, has become a lefty celebrity for his calls to demilitarize immigration enforcement, legalize marijuana, and banish donations from political-action committees. Sinema, by contrast, has started no such national firestorm. “She’s not hitting the progressive G-spot in the way that people want,” as one political operative in the state wryly put it.

To some extent, Arizona has its own test case of this progressive Democratic vision this year, which played out 200 miles away on the day Sinema was in Yuma. Bernie Sanders had come to town to campaign for David Garcia, the Democratic nominee for governor. Throngs of screaming students packed into an auditorium at Arizona State University, near Phoenix; a line of disappointed latecomers stood along the barrier gate outside, hoping to glimpse the 77-year-old democratic-socialist senator. As Sanders worked the crowd at the end of the event, Garcia trailed him a little awkwardly, hoping to catch some of the students’ outstretched hands.

Garcia is the education guy in this election: He has closely aligned himself with the “Red for Ed” movement that led thousands of teachers to strike for higher salaries and better funding for their schools, creating a major challenge for the current governor, Doug Ducey. His rhetoric on immigration is left of Sinema’s: He has called for the abolition of Immigration and Customs Enforcement, the federal agency that enforces immigration laws, and his campaign strategy has focused on mobilizing Latinos and young people. His approach appealed to Anahi Montes Lima, a 19-year-old first-time voter from Wittmann, Arizona, who didn’t know much about Garcia before the rally. “To know that there’s people that support Muslims, and also people like me, like immigrants, makes me feel good,” she told me.

Even though they’re both Democratic candidates for statewide office in Arizona this year, Sinema and Garcia have refused to endorse each other. When I asked Garcia about this backstage at the rally, he challenged the premise of my question. “I have no idea what disunity you’re talking about, to be frank with you,” he said. “I think it’s a Bernie-Hillary narrative that people are trying to play up.” Their campaign visions complement each other, he said, and the Democratic Party “has a lot of different faces to it.” Ultimately, though, he believes that “standing with … the communities most affected” by state-level policies “is what’s going to get people out to vote.”

When I asked Sinema whether she was worried about losing progressive voters with her centrist campaign, she answered, “I don’t at all.”

“Folks are so excited … that we’re attracting support from Democrats, Republicans, and independents,” she said. “In Arizona, folks don’t really care what letter is behind your name. They just want you to deliver real results for them, because we’re super practical and we’re very pragmatic people.”

Sinema wasn’t always so militantly centrist; in fact, quite the opposite. In the early 2000s, she was an outspoken Iraq War protester and Green Party supporter. She wore tutus to rallies and called herself a “Prada socialist,” joking about her lefty politics and love of fashion. In a recent debate, McSally accused her of “treason” based on a 2003 radio interview, in which Sinema seemed to say she didn’t care if Americans went overseas and fought with the Taliban. Her political opponents have pushed out clips of her speaking at progressive conferences like Netroots Nation, where she described Arizona as “the meth lab of democracy” (a line apparently cribbed from The Daily Show), or another where she called both her state and Republicans “crazy.”

[Read: John McCain and the lost art of decency]

Today, however, Sinema portrays herself in the mold of John McCain, whose recent funeral was a lament to the death of statesmanship, or Jeff Flake, the retiring Arizona senator who publicly fretted over the divisiveness of Brett Kavanaugh’s confirmation to the Supreme Court. “What’s wrong with Washington, D.C., is that people have chosen to take partisan positions rather than just doing what’s right for their community and for their state and for their country,” she told a group of supporters in Yuma. “We should be electing responsible people who are willing to engage in a bipartisan relationship, regardless of the issue.”

Sinema worked rooms full of supporters at campaign events in Yuma with a mix of inoffensive banter and studied earnestness, eagerly taking notes and performing her role as state encyclopedist as she shared facts about Arizona’s cotton industry and health-care structure. She confessed, with a hint of pride, to criticizing leadership in both parties for their partisanship: This summer, she told Politico she wouldn’t vote for Chuck Schumer to lead the Senate if she were elected. For Sinema, it’s probably also a source of satisfaction that she has voted with Trump’s agenda 62 percent of the time, according to an estimate by FiveThirtyEight, including on bills like Kate’s Law, which would increase the maximum jail time for immigrants who reenter the country after being deported or committing crimes.

For some progressive Democrats in the state, however, Sinema’s centrism is unsatisfying.

“I’m baffled why she hasn’t come out in support of David Garcia,” said Julie Gunnigle, a Democrat from Scottsdale running for the state House, at the ASU rally. “I just don’t believe Sinema is that progressive.” Gunnigle wants Sinema to be elected, but “there are things I’d like to hear come out of her mouth,” she said, including support for “Medicare for all” and campaign-finance reform. Zaira Livier, a progressive activist I met in Tucson, went further: “I’ve been trolling the hell out of Democrats online,” she said. “One of my posts was like, ‘I’m not voting for Kyrsten Sinema. Die mad about it.’”

One of the perennial problems for Democrats in Arizona is turnout: Ostensibly deep-blue parts of the state, like the area south of Tucson, tend to have very low voter participation. Joel Feinman, the head of the Pima County Public Defender’s Office, argued that state party officials have taken the wrong lesson out of this. “The reason people aren’t voting isn’t because Democrats aren’t conservative enough,” he said. “The reason people aren’t voting is that we don’t fucking stand for anything anymore.”

Although Sinema seems to have won over some of the state’s moderate Republicans, she’s still a Democrat. She has pounded McSally for voting in Congress to weaken protections for people with preexisting conditions, and her fund-raising emails are full of alarm about Mitch McConnell’s plan to take her down. The state’s GOP establishment is highly skeptical of her political past. “We’ve watched a very skilled political woman who has grown into and had her eye on the ball for a long time of what she wanted,” said Lisa James, a political consultant who oversaw George W. Bush’s reelection effort in Arizona in 2004. “She likes to say now that she’s evolved over time. I think she’s disguised over time.”

[Read: What John McCain’s death means for Republican control of the Senate]

Polling—and political coffers—suggest that Sinema has a fighting chance of winning her Senate bid, or at least wrestling it to a close finish. She has brought in nearly $15 million in contributions to her Senate race, according to the Federal Elections Commission. This compares with Garcia’s $2 million, which Ducey has outspent many times over. While polling averages put the Senate race as a toss-up, Garcia is trailing by double digits in the gubernatorial election.

“Has there been some pushback [on Sinema]? Yes,” said Steven Slugocki, the Democratic Party chairman in Maricopa County, the area surrounding Phoenix where nearly 60 percent of the state’s registered voters live. “However, I do believe, just like in 2016, the overwhelming majority of people see the alternative as far, far worse.”

The country’s progressives might not be fainting with Sinema-mania in the same vein as Beto-mania. But at least in the deserts of Yuma County, the congresswoman has some big fans. Roughly 50 or 60 volunteers, many of whom were old and white, gathered on Tuesday at Yuma’s Democratic Party headquarters to hear her speak. An 83-year-old resident, Dave Parsons, fantasized that Sinema might be part of the next bipartisan initiative on immigration reform, similar to 2013’s ultimately failed “Gang of Eight” negotiations. After the event, as she and I talked, the volunteers started a chant of “Si-ne-ma! Si-ne-ma!”

Sinema came out to the desert because she thinks she can reach the whole state with her campaign—literally, but also metaphorically. “It doesn’t matter if you live in Tucson, Yuma, Bisbee, on the Navajo Nation, Prescott, or Phoenix,” she told me, with a practiced politician’s smile. “We share some core concerns.”

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